What email address or phone number would you like to use to sign in to Docs.com?
If you already have an account that you use with Office or other Microsoft services, enter it here.
Or sign in with:
Signing in allows you to download and like content, and it provides the authors analytical data about your interactions with their content.
Embed code for: Water - Lesson 2
Select a size
(Lesson 2 in your textbooks)
Earth’s dominant feature
71% of surface covered in water
How many oceans does Earth have?
Basins – large, water-covered areas between the continents (a more accurate term to describe oceans)
97% of all water is salty. Of the 3% that is fresh, only about 1% is liquid (the rest is ice – glaciers and icebergs)
Most living organisms are largely composed of water. By mass, Marine organisms are approximately 80% made of water.
The Earth System
The interactions of these 4 aspects of the earth system create our planet’s climate and establish conditions unique to each biome and ecosystem.
The ocean as resource
Most uses of the ocean are renewable resources: the ocean replenishes itself
Some resources, like oil, natural gas, and minerals are nonrenewable
Overfishing -describes an event where a species is harvested to the point when its species is either extinct or the numbers are too small for harvest to be significant.
Types of Water
Distilled – pure water with all dissolved salts and minerals removed
Tap water – Fresh water with some minerals and treatments to kill bacteria and remove pollutants
Salt water – water that contains dissolved salts
Ice – Water in the solid state (Not to be confused with “Dry Ice”: Frozen Carbon Dioxide)
Hydrogen Bonding and Polarity
Density. Ice floats!!!
Density: Ratio of mass to volume of a substance
Why is ice LESS dense as a solid?
Density of Fresh vs Salt
Density of Freshwater: 1.00 g/cm3
Density of Salt water: 1.03 g/cm3
Salty water “sinks” in fresh water.
Since saltwater is more dense, the same objects (like an egg) will float easier in saltwater than in freshwater.
Density Practice Problem
Equation: D (g/cm3)= m (g) / V (cm3)
What is the Density of Gasoline if you have 37.5 g and a volume of 50 mL? (note: 1 mL = 1 cm3 )
What is the mass of gold if you have 100 cm3 and you know the density of gold is 19.2 g/cm3?
What is the volume of your sample of Antifreeze if you know the density is 1.02 g/cm3 and the mass of the sample is 200 g?
Independent vs Dependent variables
A variable is anything that changes
The Independent variable is established/manipulated by the experimenter. (on a graph, it is usually the x-axis)
The dependent variable is something that changes in response to the independent variable. (usually the y-axis).
In this experiment, what is the independent variable? What is the dependent variable?
Phase change: Saltwater vs Fresh
Freezing/melting Point (oC)
Boiling Point (oC)